diff --git a/README.md b/README.md
index 432e4cb3..8256ff4a 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ This README is being written.
 
 ## Requirements
 
-* Windows: Windows Vista or newer
+* Windows: Windows Vista SP2 with Platform Update or newer
 ** At present, you must provide a manifest file
 * Unix: GTK+ 3.4 or newer
 * OS X: OS X 10.7 or newer